1. Field of the Invention
The present invention relates to a resist pattern swelling material, a method of forming a microscopic pattern, a method of manufacturing a miniaturized device and a method of manufacturing a semiconductor device and more specifically to a technique for swelling a pattern provided on the resist exceeding the exposure limit by providing a film on the surface of resist pattern formed through the exposure and then swelling the resist pattern through reaction between the resist pattern and the relevant film.
Predominantly because of maintaining high productivity, utilization of light for resist exposure is still highly demanded even at present wherein a pattern tends to become further microscopic size. Therefore, not only investigations have been continued for the deep ultraviolet ray having a shorter wavelength to be used as the exposing light but also various searches have been also been continued for the mask pattern itself and shape of light source or the like. As explained above, new development of a method to easily realize extensive use of the light in the exposure to draw a more microscopic pattern is still highly demanded for the manufacturers of semiconductor devices.
2. Description of Related Art
The deep ultraviolet ray has been put into the practical use as the light to be used for exposing a photo-resist and a microscopic pattern of a certain degree can be drawn through employment of KrF (krypton fluoride) excimer laser beam (wavelength: 248 nm). Since the technique called ‘RELACS’ which enables easier drawing of a further microscopic resist pattern by utilizing this KrF (krypton fluoride) is already proposed, this method will be introduced below.
Japanese Unexamined Patent Publication (Kokai) No. 10-73927, published on Mar. 17, 1998, discloses a method. In this method, a resist pattern is first obtained by exposing the photoresist which may be exposed with the KrF (krypton fluoride) excimer laser beam. Next, a film is formed to cover the relevant resist pattern and this film reacts with a resist material at the interface thereof. Thereby, the resist material is swelled and a microscopic hole, for example, in the case of a hole pattern, can be formed exceeding the limitation of exposure. The related art explained above discloses that any type of positive or negative resist materials can be used, a novolak resin and a photosensitive agent based on naphthoquinone diazido may be listed and a chemical amplification type resist including acid generation mechanism can also be applied. This related art also discloses that polyacrylic acid, polyvinyl acetal, polyvinyl pyrrolidone, polyvinyl alcohol, polyethylene imine, polyethyleneoxydo, sthylene-maleic acid copolymer, polyvinyl amine resin, polyallylamine, water-soluble resin containing oxazoline group, water-soluble melamine resin, water-soluble urea resin, alkyd resin, sulfone amide resin or the like are effective in regard to the resin compositions used to form a film, any limitation is not provided when mixing with a water-soluble cross linking agent is possible if cross linking reaction is generated or not generated under the existence of an acidic element, and these material listed above can also be used as a discrete material or mixed material. In addition, the related art explained above also discloses that the cross linking agents based on urea such as urea, alcoxy-methylene urea, N-alcoxymethylene urea, ethylene urea, ethylene urea calbonic acid, the cross linking agents based on amine such as benzoguanamine and glucore can be used as the cross linking agent to form a film, but there is no particular limitation to the cross linking agent based on amine and any type of a water-soluble cross linking agent which forms a cross linking with acid can be used.